Justus a



(No Model.)

. J. A'. TRAUT.

SPIRIT LEVEL.

No. 421,786 Patented Feb. 18, 1890.

540M672 M Am I UNITED STATES PATENT FFICE.

JUSTUS A. TRAUT, OF NEW BRITAIN, CONNECTICUT, ASSIGNQR TO THE STANLEYRULE AND LEVEL COMPANY, OF' SAME PLACE.

SPIRIT-LEVEL.

SPECIFICATION forming part of Letters Patent No. 421,786, dated February18, 1890.

Application filed December 12, 1889. Serial No. 333,453. (No model.)

To all whom, it may concern.-

Be it known that I, J UsTUs A. TRAU'I, a citizenof the United States,residing at New Britain, in the county of Hartford and State ,ofConnecticut, have invented certain new and useful Improvements inSpirit-Levels, of which the following is a specification.

The invention relates to improvements in spirit-levels of the classhaving adjustable spirit-tubes; and the object is to provide a simple,cheap, and desirable mounting for the spirit-tube, whereby it willremain in place, after it has been properly adjusted, without strainingany of the parts; also, to provide more simple and convenient means forobserving when the air-bubble is at the highest part of the tube.

Referring to the accompanyingdrawings, Figure 1 is a plan view of theface-plate and tube of a level. Fig.2 is a perspective view or cornerelevation of the parts; and Fig. 3 is an end view of the same.

In the views, the letter a indicates the face-plate, which is cut orstamped from sheet metal and provided with the usual observation-slot band screw-holes 0, whereby it may be secured to the stock over therecess in the customary manner. An ordinary -spirit-tube d is embeddedin the case or box the ends of which are provided with an extension orlug 6 6 supported by a bracket f, which is attached to the under side ofthe face-plate near one end, while the lug e is tapped and threaded andsupported by a screw g, which passes through the face-plate into thethreaded socket in the lug. The lug c is preferably formed triangular incross-section and sets into a triangular socket, slightly larger, in thebracket f, so that under the influence of the spring h, interposedbetween the bottom of the face-plate and the upper surface of the lug e,the lug is firmly held in the socket central of the plate, in order thatthe tube shall be directly under the observation-slot b. A spring 11 isinserted between the faceplate and the lug e at the opposite end of thetube-case. The surface-plate is secured to the stock with the tube inthe recess, and

The lug e is loosely the tube is adjusted to the proper position by therotation of the screw g. The bracket facts as the fulcrum and freelyallows the tube-case a little oscillation when it is moved by the screwat the opposite end. As the lug e is loosely held in the socket in thesuporting-plate it is free to slide longitudinally and adjust itself, sothat the face-plate will not bind or buckle, and the parts will not besubjected to any undue strain.

In order to provide a ready means for observing the position of theair-bubble in the tube, the edges of the observation-slot b, whichextends longitudinally of the faceplate, are notched or indentedtransversely of the face-plate over the highest portion of the tube, sothat the highest part is readily indicated whether the level is belowthe eye, above the eye, or turned at an angle, as shown in Fig. 2. Theindentures also widen the slot, making the index the widest part of theslot in the face-plate, not only carrying the index farther toward thesides, but letting in the most light at the index-point, thereby makingthe observation much 'more convenient from various points than in alevel with the ordinary index-mark on the glass tube or than a levelwith a projecting point on one side of the slot in the face-plate at themiddle of its length.

I claim as my invention 1. In combination with the face-plateof a level,a depending bracket having a perforation, a tube-case bearing aspirit-tube having a lug at one end extending loosely through theperforation in said bracket, and having a threaded lug at the oppositeend, an adjListing-screw passing through the faceplate and into saidthreaded lug, and a spring between said lug and face-plate,substantially as described,and for the purpose specified. r

2. In combination with the face-plate of a level, a tube-case bearing aspirit-tube, one end of the tube-case being triangular in cross-sectionand supported in a triangular slot in a bracket depending from the underside of the face-plate, the opposite end of the tube-case being providedwith a threaded socket and supported by a screw which passes I are eachprovided with an indenture, subthrough the face plate into the threadedstantially as specified. socket, substantially as specified.

3. The combination, with the tube-ease of 5 a spirit-level, of aface-plate provided with a Witnesses:

longitudinal observation slot, the opposite GEORGE U. TRAUT, edges ofwhich near the middle of its length CHAS. '13. STANLEY.

J USTUS A. TRAUT.

